Elevator latch



IR. KQHERTEL Jan. 11, 1938.

ELEVATOR LATCH Filed May 9, 1936 2 Sheets-Sheet 1 BY ATTORNEYS Jan.11,193s.. R. K. HERTEL v ,105,0

' ELEVATOR LATCH FilGd May 9, 1936 2 Sheets-Sheet 2 i/ TTORN S Patented Jan. 11, 1938 UNITED STATES ELEVATOR LATCH Richard K. Hertel, Vernon, Calif., assignor to Byron-Jackson 00., Los Angeles, Calif., a corporation of Delaware Application May 9, 1936, Serial No. 78,830

5 Claims.

. This invention relates to elevators for supporting pipe, casing or the like while it is being raised or lowered in a Well and more particularly to slip type elevators employing wedge-shaped slips for gripping the pipe.

An object of the invention is to provide an improved latch for an elevator, which latch is simple and relatively inexpensive to make while at the same time being convenient to operate and safe in use.

In slip type elevators the weight of the pipe: acting upon the slips produces powerful radial forces tending to open the elevator and these forces must be opposed by the latch. The latter therefore must be positively locked against disengagement or release While a pipe is being supported and must be capable of withstanding great strains. r V

Heretofore rather complicated latch mechanisms have often been resorted to for slip elevators in order to satisfy the safety requirements.

However, it is also an important requirement of an elevator latch that it be possible to quickly and positively operate it, and as a rule complicated latch structures do not satisfy this requirement.

In accordance with the present invention, I have devised a relatively simple latch construction which is rugged, safe and easily operated. It will now be explained in detail with reference to the accompanying drawings.

In the drawings:

Fig. 1 is a plan view of an elevator incorporating a latch in accordance with the invention, that portion of the elevator involving the latch being shown in section;

Fig. 2 is a front elevation of a portion of the elevator shown in Fig. 1 to better illustratesome features of the latch construction; and

Fig. 3 is a detail plan view of a portion of the elevator showing the latch structure, the view being similar to Fig. 1 but showing the latch and elevator in partially opened positions.

Referring first to Fig. l, the elevator therein depicted is of the side door type comprising a body member I having a pair of lugs or trunnions 2 thereon adapted to be engaged by links for supporting the elevator, and, a door 3 hinged to the body I by a hinge pin 4. The body member I and the door 3 constitute jaws adapted to be closed about a pipe. The inside surfaces 5 and 6 of the jaws are substantially conical in shape,

tapering inwardly and downwardly and serve as seats to support wedge-shaped slips 1, only one of which is shown in Fig. 1. However, in the particular model shown there would be four slips altogether, two onrthe body I and two on the ate 3. A slip setting lever 8, which is pivotally mounted by means of a pin 9 on the top of the door 3, is provided forsetting the slips. Thus 5 the bifurcated inner end of the lever 8 is positioned above one of the slips 1, as shown in Fig. l,

' so that if the handle II] of the lever 8 is pulled outwardly the slip is forced downwardly on its tapered seat, causing it to move inwardly on a pipe positioned within the elevator. All of the slips are linked together so that they move up and down in unison. However, the specific arrangement and mounting of the slips is of no interest in connection with the present invention and for that reason will not be described in detail. As previously indicated, the door 3 is hingedly attached at one end to one end of the body mem-. her I by the hinge pin 4. When the door is in closed position it is adapted to be locked in closed v position by a latch I2 which is pivotally mounted on the end of the body member I opposite the door hinge pin 4 by a latch pin l3 so that it is free to swing in a horizontal plane. This latch I2 cooperates with a. lug or shoulder [4 on the door 3.

As shown to best advantage in Fig. 2, the latch I2 comprises upper and lower arms I5 and I 6, respectively, which engage the hinge pin I3 adjacent opposite ends of the latter. The hinge pin in turn engages a hinge lug on the body mem her I, which lug is positioned intermediate the latch arms [5 and IS. The latch arms are reinforced and maintained in proper spaced relation adjacent the hinge end-thereof by a strut I! and are joined at their outer ends by a handle portion, [8 and a lug engaging portion I9. This lug engaging portion 19 is provided with a face 20 which is approximately normal to a radius drawn from the axis of the pin I3 and engages a face 2| on the lug or shoulder I4 when in closed position, the latch being shown in closed position in Fig. 1. It is to be understood, however, that the surfaces 20 and 2 I, instead of being substantially flat as shown in the drawings, may be slightly .curved so that they are substantially concentric with respect to the axis of the pin I3. A portion of the latch face 20 is cut away to form a slot 22 to permit the latch to clear a door-closing lever 23 when the latch is swung open.

To retain the latch I2 in the closed position shown in Fig. 1, a latch locking lever 24 is pro- .vided, this lever being pivotally mounted by a pin 25 on the door 3 so that it swings in a horizontalplane. The long end 26 of the latch locking lever 24 is normally urged inwardly toward the door by a helical compression spring 21 which is interposed between the short end 28 of the lever and the adjacent surface of the door.

To restrict the arc of movement of the looking member 24, a finger 29 is provided thereon, which finger is adapted to contact the surface of the door when the end 26 is moved a'predetermined distance toward the door and a finger 30 is provided on the door 3 adapted to contact the short end 28 of lever 24 when that end is moved inwardly a predetermined distance. As shown to best advantage in Fig. 2, the long arm 26 of lever 24 is bifurcated and the outer ends of the two portions thereof are joined by a bar 3I and a handle 32. The bar 3I, as clearly shown in Fig. 1, is adapted to engage a lug I9I on the latch I2 when the latter is in closed position and thereby retain the latch in closed position.

Elevatorsof the type described are often made in relatively large sizes to handle pipe and casing of large diameter. As a result, the parts are relatively heavy and sometimes offer considerable resistance to manual manipulation. Thus it is sometimes difficult to fully close the door 3 of the elevator about a pipe. To facilitate closing the door, a door-closing lever 23 (previously mentioned) is provided, this lever being pivotally mounted by a pin 36 between the bifurcated end of an extension 31 on the body member I, this extension extending between the upper and lower portions I5 and I6, respectively, of the latch I2. The outer end of the lever 23 is provided with a handle 38 and the inner end 39, which is the short end, is adapted to engage a shoulder 40 on the door 3 (Fig. 3) so that by pulling on the handle 38 the end 39 may be brought to bear against the shoulder 40 and force the door into fully closed position. To limit travel of the lever 23 the latter has pivotally secured thereto as by a pin 42 a finger 43, the end of which is adapted to bear against the adjacent portion of the body member I when the lever is swung through a predetermined distance. A helical compression spring 44 surrounds the finger 43 and constantly urges the lever 23 into the retracted position shown in Fig.1. The limit of movement in this direction of the lever 23 is fixed by a shoulder 45 on the body member which bears against the lever.

The mechanism described is operated as follows: Referring first to Fig. 3, assume that the elevator has been positioned about a pipe to be lifted and the door 3 is to be closed. Closing movement of the door is ordinarily effected by grasping the latch handle I8 in the left hand and grasping a door handle 46 (which is secured directly to the door 3) in the right hand and swinging the door shut. In some instances the door will readily move into fully closed position, under which conditions it is locked in closed position immediately by moving the latch I2 toward the door 3 until its face 2|] engages the face 2| on the lug I4 of the door. Final closing movement of the latch I2 causes the lug I9I to bear against the curved surface 41 of the latch looking bar 3| and deflect the latter outwardly sulficient to permit the lug I9I to move therepast, after whichthe locking lever 24 is again urged into closed position (as shown in Fig. l) by the spring 21 to engage the lug I9I on the latch I2 and hold the latter positively in closed or locked position.

However, in some instances it is difficult, if not impossible, to fully close the elevator door by applying closing force directly to the door handle 46. Under these conditions the operator, having failed to fully close the door by pulling the handles 46 and I8 toward each other, releases the latch handle I8 and grasps the handle 38 on the lever 23 and pulls forwardly on the latter. This causes the inner end 39 of the lever to engage against the face 49 on the door and forces the latter into fully closed position, whereupon the operator releases the handle 38 and grasps the latch handle I8, pushing the latch into closed position, the latch lock 2 snapping over the lug I9I as previously described to maintain the latch in closed position.

When the elevator is to be removed from a pipe, the latch is first released by pulling out on the handle 32 to disengage the latch locking bar 3| from the latch lug IBI. Thereafter the latch handle I8 is grasped and pulled outwardly and disengages the latch from the lug I4, after which the door handle 46 is grasped and pulled outwardly to swing the door open.

Various modifications can be made in the particular latch structure described without departing from the invention and the particular construction described is merely illustrative. The invention is therefore to be limited only to the extent set forth in the appended claims.

I claim:

1. An elevator comprising pivotally connected jaws, a main latch member pivotally supported on one of said jaws, a lug on the other jaw adapted to be engaged by said main latch memher when the jaws are closed and said latch is swung against the said other jaw, a shoulder on said latch, an auxiliary latch pivotally supported on the said other jaw and adapted to engage said shoulder on said main latch when said jaws are closed and said main latch engaged, lever means pivotally supported on said one jaw for movement about an axis parallel to the axis of movement of said main latch, one end of said lever extending outwardly from said jaw and terminating in a handle, an auxiliary shoulder on said other jaw, the other end of said lever 1 being positioned to engage said auxiliary shoulder when said jaws are almost but not quite closed, whereby said jaws can be urged toward fully closed position by pulling the handle of said lever.

2. An elevator as described in claim 1 with spring means for normally maintaining said lever in retracted position out of engagement with said auxiliary shoulder.

3. An elevator comprising pivotally connected jaws, one of said jaws having a hinge lug on the free end thereof, a main latch member comprising a pair of separated arm members positioned above and below said hinge lug on said one jaw and pivotally connected thereto by a pin extending through the said arms and lug, the outer end of said arms being rigidly connected with a latching bar, a lug on the other jaw adapted to be engaged by said main latch bar when the jaws are closed and said latch is swung against the said other jaw, auxiliary latch means pivotally supported on the said other jaw, and a shoulder on said main latch adapted to be engaged by said auxiliary latch when said jaws are closed and said main latch is in closed position, said hinge lug on said one jaw extending beyond the hinge pin connecting it to said latch member between said latch arms, and lever means pivotally supported on said lug intermediate said latch arms for movement about an axis parallel to the axis 15 of movement of said latch, one end of said lever extending outwardly from said jaws and terminating in a handle, and an auxiliary shoulder on said other jaw, the other end of said lever being positioned to engage said auxiliary shoulder when said jaws are almost but not quite closed, whereby the jaws can be urged toward fully closed position by pulling the handle of said lever.

4. An elevator comprising pivotally connected jaws, a main latch member pivotally supported on one of said jaws, a lug on the other jaw adapted to be engaged by said main latch member when the jaws are closed and said latch is swung against the said other jaw, said latch member and lug having cooperating contact faces substantially normal to' a radius extended thereto from the axis of said latch member, when the jaws are in closed position, a shoulder on said main latch member, and an auxiliary latch pivotally supported on the said other jaw adapted to engage said shoulder on said main latch when said jaws are closed and said mainlatch is engaged with said lug.

5. An elevator comprising pivotally connected jaws, a main latch comprising a single rigid latch member pivotally supported on one of said jaws, a lug on the other jaw adapted to be engaged by said rigid latch member when the jaws are closed and said latch is swung against the said other jaw, said latch member and lug having cooperating contact faces substantially normal to a radius extended thereto from the axis of said latch member when the jaws are in closed position, a shoulder on said rigid latch member, an auxiliary latch pivotally supported on the said other jaw adapted to engage said shoulder on said rigid latch member when said jaws are closed and said main latch is engaged with said lug, and spring means for urging said auxiliary latch into locking position, said auxiliary latch and main latch having cooperating tapering contact surfaces thereon whereby said auxiliary latch is automatically opened against the tension of said spring in response toclosing movement of said main latch and is thereafter closed by said spring in response to completion of closing movement of said main latch.

RICHARD K. I-IERTEL. 

